I don't know the answer for sure but have a couple of things to try:
1. Change the bootpage paramater to remove the GS=1 flag. You could use TiVoWeb to do this ("PAL NTSC" -> "Set PAL") or alternatively use the methods described in this HowTo:
2. /etc/rc.d/rc.sysinit.author includes these lines:
You could uncomment the line with fixup30.tcl.
# Keep Guided Setup from bothering us
# Actually, we want GS to bother us...so comment it out
BTW the TiVo nags you when it doesnt have guide data.
Hope this helps.